I've seen this discussed before, as in, which is better (particularly pre-C4 vs WC), but I haven't seen comments on doubling up in these larger sizes, so here goes.

I have a BD C4 #5 and #6, both of which I like. I'd like to double up on the #5 soon, and eventually the #6. Is there any advantage to getting the WC #5 as my double, i.e., do the WC #5 and #6 compliment the corresponding BDs well? I've heard mixed responses about one pushing better, and being less prone to walking when you climb past it, than the other, and maybe that the sizes are slightly different, but the picture isn't clear. None of my partners climb on the WC large cams, so I haven't had a chance to play with one, let alone place one.

Personally I think the double axle on the BD is superior and the cam lobes are less likely to invert, twist, and become jingus if accidentally bumped with a foot, arm, or rope in the crack. Most of the times it's not an issue, but every now and then it gets weird. The WC 6 is rumored to be better in the "tipped out" position than the BD, (probably because it's wider) but it's hard to say exactly.